fix test and dartfmt

packages/image_picker/image_picker_for_web/example/integration_test/image_picker_for_web_test.dart

@@ -31,7 +31,7 @@ void main() {
 
     final overrides = ImagePickerPluginTestOverrides()
       ..createInputElement = ((_, __) => mockInput)
-      ..getFileFromInput = ((_) => textFile);
+      ..getMultipleFilesFromInput = ((_) => [textFile]);
 
     final plugin = ImagePickerPlugin(overrides: overrides);
 
@@ -52,7 +52,7 @@ void main() {
 
     final overrides = ImagePickerPluginTestOverrides()
       ..createInputElement = ((_, __) => mockInput)
-      ..getFileFromInput = ((_) => textFile);
+      ..getMultipleFilesFromInput = ((_) => [textFile]);
 
     final plugin = ImagePickerPlugin(overrides: overrides);
 

packages/image_picker/image_picker_for_web/lib/image_picker_for_web.dart

@@ -311,12 +311,6 @@ typedef OverrideCreateInputFunction = html.Element Function(
   String? capture,
 );
 
-/// A function that extracts a [html.File] from the file `input` passed in.
-@visibleForTesting
-typedef OverrideExtractFilesFromInputFunction = html.File Function(
-  html.Element? input,
-);
-
 /// A function that extracts list of files from the file `input` passed in.
 @visibleForTesting
 typedef OverrideExtractMultipleFilesFromInputFunction = List<html.File>
@@ -330,9 +324,6 @@ class ImagePickerPluginTestOverrides {
   /// Override the creation of the input element.
   late OverrideCreateInputFunction createInputElement;
 
-  /// Override the extraction of the selected file from an input element.
-  late OverrideExtractFilesFromInputFunction getFileFromInput;
-
   /// Override the extraction of the selected files from an input element.
   late OverrideExtractMultipleFilesFromInputFunction getMultipleFilesFromInput;
 }